Wednesday, October 21, 2009

As with the case of yellow pond lily (Nuphar polysepala), a suite of related wetland plants once occurred in the central coastal region of California. One of these is Buckbean (Menyanthes trifoliata), an aquatic plant that is infrequent in the Sierra Nevada. Buckbean is distributed throughout the northern hemisphere of Earth, extending south into California at its southerly distributional limit. Now, I find a report [A. J. Plater et al. 2006. Climate and human impact on lowland lake sedimentation in Central Coastal California: the record from c. 650 AD to the present. Reg. Environ Change 6: 71–85] which records Menyanthes trifoliata from modern-era sediment records in Pinto Lake, near Watsonville. Menyanthes trifoliata was not included in the "An Annotated Checklist of Vascular Plants of Santa Cruz County, California" presumably because it was eliminated before any of the compilers of that list were born! It is yet another recent extirpation of regional wetland flora?

Dr. H.H. Behr, an early-era medical doctor of San Francisco, listed Buckbean from a marsh in San Francisco Bay [ 1888, Flora of the vicinity of San Francisco]. The same setting was known to support other circumpolar wetland plants [viz. Carex comosa, and cotton-grass, Eriophorum gracile] which are all now gone.

Interestingly, Helen K. Sharsmith collected Menyanthes trifoliata from the Mount Hamilton Range {although the record is not given in her "Flora of the Mount Hamilton Range of California, American Midland Naturalist 34:289-367. 1945], labeling her specimen "the South end of Mt. Day ridge". On the same day, Sharsmith also collected specimens of other marsh taxa from a "sag pond on the South end of Mt. Day ridge". On Google Earth there is an intact pond at 37.39131,-121.68344 which might be the location for this report. The site appears to be intact, but it needs resurvey, also.